RF-over-Fiber for Wideband Large Scale Microwave Measurements

In this paper, we investigate the design issues of microwave measurements employing RF-over-fiber technology. The transmission technology involves the usage of optical modulators to perform amplitude modulation of an optical carrier using the input microwave signal. The modulated carrier is then transmitted through an optical fiber and the microwave signal is reconstructed by demodulating the optical carrier using an RF photodetector. We present the system modeling, the choice of transmission waveform and the characterization and measurement of some of the components of the system. We verify the correct operation of the system using measurement comparison to vector network analyzer. The proposed applications are the wideband characterization of microwave systems and components and large scale measurements of radar cross sections.